土贝母皂苷对HL-60细胞周期作用的研究

Effect on cell cycle in human promyelocytic leukemia cells (HL-60) treated with tubeimosides

目的:应用土贝母皂苷(下称皂苷)作用于人早幼粒白血病细胞(HL -60),研究皂苷抗肿瘤作用的分子机制。方法:采用流式细胞术等方法分析细胞周期及凋亡;蛋白印迹免疫法检测细胞凋亡及周期相关基因 bcl- 2、cdc2 和 cy clinB1表达的变化。结果:15μmol/L皂苷作用 24 h 可将 HL -60 细胞阻滞于G2/M期,进而诱导凋亡,流式细胞仪检测肿瘤细胞出现典型的亚二倍体“凋亡小峰”。凋亡抑制基因bcl 2表达无明显变化,周期蛋白 cyclinB1 表达降低,而cdc2表达无明显改变。结论:皂苷导致HL- 60细胞 G2/M期阻滞,进而诱导凋亡;周期阻滞的分子机制与降低 cy clinB1蛋白水平有关,而凋亡的诱导与bcl- 2表达无关。

OBJECTIVE:To explore the molecular mechanism of antitumor effect of tubeimosides by treating human promyelocytic leukemia cells (HL-60). METHODS: Cell cycle and the induction of apoptosis were evaluated by the flow cytometry,and bcl-2, cdc2 and cyclin B1 expression determined by Western blot analysis. RESULTS: HL-60 cells underwent G 2/M arrest within 24 hours of exposure to tubeimosides, and some apoptotic cells were detected, and a typical subdiploid peak was observed by the flow cytometry after 72 hours. Western blot analysis of tubeimosides-treated cells revealed low cyclin B1 expressing level consistent with G 2/M arrest, as well as constant cdc2 and bcl-2 expressing level. CONCLUSIONS: Tubeimosides has in vitro activity against HL-60 cells, and this activity is associated with G 2/M arrest, the induction of apoptosis, and low cyclin B1 expressing level. These findings suggest that further evaluation of the activity of tubeimosides in HL-60 cells is reasonable and that the pharmacologic modulation of cell cycle arrest and apoptosis pathways deserves further study as a potential anticancer strategy.